Right and left hand casement crank mechanisms identified as manufactured by Truth.

Thanks for writing in! Your window balances look like they can be replaced with the 39-138 and 39-139 Single Arm Crank Operators. Take a look over the dimensions below and compare them to confirm if these are the correct replacements for your repair.

Be sure to take a look at the tracks and the handles tagged below as well.

Dimensions for 39-138